Multicylinder internal combustion engine



2 Sheets-Sheei'l 1 April 1l, 1933. E. MANDLx-:R

MULTICYLINDER INTERNAL COMBUSTION ENGINE Filed Feb. 27, 192e WMM/e April 11, 1933. E, MANDLER MULTICYLINDER INTERNAL CMBUSTION ENGINE Filed Feb. 27, 1929 2 Sheets-Sheet 2 Patented Apr. 11, 1933 UNITED rss PASTENT OFFICE EUGEN MANDILER, oF VIENNA, AUsTaIA, AssIGNoa VTo THE FIRM cLIivIAX MoToREN- f- WaR-KE UND scarrrswsasr LINZ'A. e., or VIENNA, AUSTRIA f MULTIGYLINDER INTERNAI;I coivIs'IIsTIoN ENGINE Application filed February 27, 1929, serial N0.V`a43,1e2, andra Austria November e, 192s.

This invention relates to multicylinder internal combustion engines, especially to water-cooled two stroke cycle engines, the cylinders of which are connected together' so as to form one or more blocks. In suc-h engines, the cylinders are usually directly connected together at their upper and lower ends, or they are connected together to form a rigid unit by a common cooling jacket. It is also known, rigidly to connect all the cylinders of an engine by a common cylinder cover secured by means of bolts or the like.

In such engines, the upper portions of the cylinders exposed to heat, bend, if highly heated, since the expansions due to heat, especially those perpendicular to the cylinder axis, cannot freely develop on account of the connection between the several cylinders. It is obvious that leakage between the pistons and the cylinders, a higher piston friction and other inconveniences will result from this curvature of the cylinders.

The object of the present invention therefore is'to avoid the above inconveniences by arranging the cylinders so that each of them together with its cylinder head stands freely with its upper portion exposed to heat. In connection therewith, an extremely simple and advantageous arrangement is obtained by providing a common, but removable cooling jacket having the form of a cap which is put over the cylinders. rIhis cooling jacket has oints with each of the cylinder heads, these oints being advantageously of circular form. This arrangement renders separate cooling jackets for each cylinder or cylinder head superfluous and furthermore a very good cooling of the cylinder heads is obtained. After removing the cooling jacket, the upper portions and the heads of all the cylinders are easily accessible for inspection or repair.

In the accompanying drawings, which illustrate one constructional form of the invention, by way of example: Fig. l is a longitudinal section and Fig. 2 a cross section through the engine.

Figure 3 is a perspective view of the upper part of one of the cylinders together with a portion of the cover of the common cooling jacket, Figure 4 shows the complete cover with a portion broken away and Figure 5 shows a-'three-cyli-nder block and cooling jacket with the cover removed.

A; The cylinders a form onepiece with the lower part o' of the cooling acket, but they I stand freely with. their upper portions, that is to say', above the openings of the air inlet port wand the exhaust port Z. Also the cylinder heads ZJ secured by means of bolts are not connected together. It is obvious that each of the several cylinder heads may also form one piece with its cylinder.v rIhe cooling space is completed by a cap c havingcir-V cular joints with each cylinder head I). These joints, not being rigid,'enable the c ylinders to expand freely. For this purpose a' little free radial play L, which is shown on an exaggerated scale in Figure 3 is provided between the cylinder heads b and the holes of the cap c, into which the heads enter, while a iiexibility of these joints in the direction of the cylinder axis is obtained by the interposed yielding joint rings (l, made for instance of rubber or the like.

All the bores f for the fittings, such as valves, nozzles and the ignition devices, are placed within the joint rings CZ. By these means the said bores do not pass the cooling Water space, so that special joints are not necessary f-or the-in. Furthermore, the cap c can be removed without removing the said fittings.

Y What I claim is:

l. In a multi-cylinder internal combustion engine of the two stroke cycle type, a cylinder block comprising a plurality of cylinders open at their upper ends and cast together in one piece, said cylinders having their upper ends exposed to heat extending freely, so as to be capable of expanding without constraint under the action of heat, and separate cylinder heads secured to the said cylinders, as and for the purposes set forth.

2. In a. multi-cylinder internal combustion engine of the two stroke cycle type, a cylinder block comprising a plurality of cylinders, open at their upper ends, separate cylinder heads secured to the said cylinders, a common cooling water jacket removably secured to said cylinder block so as to extend over al1 

